Replacement Pella storm door latch

I want to replace some or all of the parts of a Pella storm door latch (Pella branded) shown in uploaded photos. The exterior handle and cover plate are weathered (storm door handle 1) and I want to replace them for appearance sake, with either polished brass or white finish parts. The latch operated by an exterior lever and an interior push lever (storm door handle 4) seems worn. The interior part of the lock (bottom of storm door handle 3 seems fine and may not need replacement.
What should I order?